Section 870. Office of payroll administration

There shall be an office of
  payroll administration which shall be headed by two directors  appointed
  by  the mayor, one of whom shall be appointed upon the recommendation of
  the comptroller. The directors may be city employees. They shall receive
  no compensation for their services to the office  (except  that  a  city
  employee  may  continue  to  receive  regular compensation) but shall be
  compensated for  expenses  actually  and  necessarily  incurred  in  the
  performance of their duties.